Abstract |
Angiogenesis, the formation of new capillaries from existing vessels, increases oxygenation and nutrient supply to
ischemic tissue and allows tumor growth and metastasis. As such, angiogenisis targeting provides a novel
approach for cancer treatment with easier drug delivery and less drug resistance. Therapeutic anti-angiogenesis has
shown impressive effects in animal tumor models and are now entering clinical trials. However, the successful
clinical introduction of this new therapeutic approach requires diagnostic tools that can reliably measure
angiogenesis in a noninvasive and repetitive manner. Molecular imaging is emerging as an exciting new discipline
that deals with imaging of disease on a cellular or genetic level. Angiogenesis imaging is an important area for
molecular imaging research, and the use of radiotracers offers a particularly promising technique for its
development. While current perfusion and metabolism radiotracers can provide useful information related to tissue
vascularity, recent endeavors are focused on the development of novel radioprobes that specifically and directly
target angiogenic vessels. Presently available probes include RGD sequence containing peptides that target αv β3
integrin, endothelial growth factors such as VEGF or FGF, metalloproteinase inhibitors, and specific antiangiogenic
drugs. It is now clear that nuclear medicine techniques have a remarkable potential for angiogenesis imaging, and
efforts are currently continuing to develop new radioprobes with superior imaging properties. With future
identification of novel targets, design of better probes, and improvements in instrumentation, radiotracer
angiogenesis imaging promises to play an increasingly important role in the diagnostic evaluation and treatment of cancer and other angiogenesis related diseases. (Korean J Nucl Med 38(2):171-174, 2004) |